Several Technical Research On Nuclear Magnetic Resonance Instrument

In recent years, with rapid scientific and technological development, more extensiveapplication of nuclear magnetic resonance imaging techniques are used in geology, chemistry,medicine and other fields. It not only can be used for measuring nuclear magnetic moment, butalso studying the structure of the nucleon. Using NMR T1T2spectrum as a technical means toanalyse substances, it will not damage the internal structure of the sample, and image fast,accurate, have a good resolution. It plays an unprecedented role in the various disciplines.Espicially in the check human disease field it has become a kinds of powerful weapons. AsT1T2spectrum directly affecting the image quality, it is necessary to carry out in-depth study，Based on nuclear magnetic resonance instrument widely research, this paper studies thefollowing two aspects.On the inversion of NMR relaxation signal basic theory research andanalysis, this paper discusses the T2relaxation signal inversion optimization method.Optimization T2spectrum of nuclear magnetic resonance (NMR) signal is according to thebasic theory to construct the inversion of the objective function, then convert the targetfunction of nuclear magnetic resonance T2spectrum inversion for the minimum value problemto solve the objective function, using the conjugate gradient method secondary termination andthe advantages of faster convergence to complete the above optimization problem. It has acareful and detailed discussion for the method. Theory of echo data and signal-to-noise theoryecho data were compared. Finally，the optimal inversion algorithm is fully applicable to thelow signal-to-noise ratio of the nuclear magnetic relaxation signal inversion data echo train,with a strong anti-interference ability and low demands on the initial point.By MRI imaging artifacts, the paper puts forward a kind of image blind restorationalgorithm based on image quality assessment. This method analyzes the blind restorationalgorithm based on gradient projection. Blind restoration of gradient projection algorithm wasimproved. The image quality assessment is proposed to introduce which is more effective toavoid the solving process of trapped in local optimal solution or unstable situation. Iri addition,the paper puts forward a new method to scratches for secondary fuzzy which the fuzzy typewas known, then non-blind restoration of the image. Experimental results show that the method can effectively improve the image quality, get a clear image and good recovery edgeinformation. The method effectively removed scratches effect, and make the image more inline with the visual perception of people.